HR M67
B - V
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
V
18
16
14
12
10
8
6
4
2
0
-2
-4
-6
-8
-10
ZAMS
M67
dB-V = 0
dV = 0